Explosion door particularly for blast furnace gas collectors



June 5, 1962 B. KONEMUND ETAL 3,037,737

EXPLOSION DOOR PARTICULARLY FOR BLAST FURNACE GAS COLLECTORS Filed Dec. 24, 1958 v Ber/mu K emund & Pau/ Sch/ege/ Via Pw L AT TORNEYS nit tates atent 3,037,737 EXPLOSION DOOR PARTICULARLY FOR BLAST FURNACE GAS COLLECTORS Berthold Kiinemund, Dortmund-Dorstfeld, and Paul Schlegel, Dortmund, Germany, assignors to Fa. Rappold & Co., G.m.b.H., Duren-Birkesdorf, Germany Filed Dec. 24, 15958, Ser. No. 782,702 3 Claims. (Cl. 251-31) The present invention relates to explosion doors particularly for those as used in blast furnace gas collectors.

In locations which are filled with a gas as for instance blast furnace gas collectors, pipe lines, dust separators and the like, use is generally made of explosion doors consisting of a casing associated with a closing disc. The gas-tight fitting of such closing disc is effected by a pressure device acting thereon which will yield to the pressure of the explosion. Usually this closing disc is urged into place by a counterweight corresponding to the operating pressure within the space.

The contact pressure of the closing disc which is obtained by means of the counterweight has to be greater than the normal gas pressure existing at the interior side of such disc. In many cases, especially in blast furnace gas collectors, the existing high gas pressure at the interior in addition to the siZe of the disc requires a counterweight which is especially heavy.

Counterweights of this type have obvious disadvantages and in addition they have further disadvantages that when explosions occur in the gas filled space the inertia of the mass of the counterweight has to be overcome first before there is an opening of the closing disc. Since the inertia of the mass is quite large for the amount of the required counterweight, the explosion disc will open quite slowly so that the desired fast escape of the explosion gas can not take place.

If, as is usual in blast furnace gas collectors, the explosion doors are used at the same time as cowling flaps so as to remove all pressure from the gas filled space when inoperative and these flaps are used as inlet openings also, then in order to open the cowling flaps the heavy counterbalance weight must be raised and maintained in raised position. 'It is an object of the invention to remove the above disadvantages from the operation of the closing disc during explosions.

A further object of the invention is to provide a construction whereby the cowling flaps may be operated most advantageously.

A further object of the invention is to provide a construction wherein a cylinder and cooperating piston which may be operated by any fluid such as air, to serve as the counterweight for the closing disc.

A further object of the invention is to provide a construction associated with the closing disc which is perable with very little inertia so that an immediate and fast escape of the explosive gases may be obtained and the closing disc upon the termination of the explosion may be brought within a short period of time again into the closing position and maintained there.

A still further object of the invention is to provide means whereby the pressure upon a piston in a cylinder may be reversed by means of a multiway valve so that the closing disc may be more easily opened and maintained in open position.

With the above and other objects in view which will become apparent from the detailed description below, a preferred embodiment of the invention is shown in the drawing.

Referring to the drawing there is shown a casing a having a closing disc b which is suspended easily movable from the lever d by the bolt 0. The lever d is pivoted upon the axis a provided in the bracket 1. Also pivoted upon the bracket f is a cylinder i constituting part of the means for applying pressure to the closing disc b.

Reciprocatingly mounted in the cylinder 1' is a piston g having fixed thereto a piston rod h which in turn is pivotally connected at w to the free end of the lever d.

The chamber k in the cylinder i may be supplied with compressed air from the feed line I to act upon the piston g. The feed line I may be connected to a larger feed line network with a corresponding capacity.

The closing disc b will at first close under its own specific weight and then the pressure from the compressed air network need only be so high as to overcome the operational inner pressure which acts upon the interior of the closing disc in order to press the disc into gas tight, position.

When there is a sudden increased pressure or explosion which exceeds the usual interior operational pressure the piston g is driven back by the rising of the disc b into the chamber k. The compressed air within the chamber k is pressed backwardly into the compressed air network and is compressed to a minor extent. This yielding of the pressing means upon the disc b takes place immediately without any necessity of overcoming the inertia of a body such as the heavy counterweights usually employed. Furthermore the pressure is very elastic. AS soon as the temporary excess pressure at the interior of the closing disc ceases the closing disc b is again pressed gas tightly against the casing a by the compressed air acting upon the piston g.

When it is desired for instance to ventilate the operating space at the interior of the closing disc b and thereby maintain the disc b open this may be done by reversing the pressure of the compressed air upon the piston g. In this case there is provided a multiway valve p and a feed line 0 into the chamber n at the other side of the piston g. Then when compressed air passes through the line 0 the piston g will be raised in the cylinder i thereby raising the closing disc b by means of the piston rod h into open position.

The two multiway valves m and p suitably controlled by a common operating device such as the levers r and s which are connected together by a common operating rod t. By the use of the compressed air feed line with the inlet u and the outlet 1/ when the valve m is opened the chamber k is fed with compressed air through the line I and the chamber 11 is emptied thereby bringing about the closing position of the disc b. However, when the valve p is opened the chamber n receives compressed air through the line 0 and through the valve m the chamber k is emptied thereby bringing about the open position of the disc b.

The cylinder 2' is preferably swiveled on an axis transverse to its longitudinal axis so that at the closing position of the disc b in correspondence with the different requirements of energy the effective radius 2 through which the piston rod it operates is as large as possible while in the open position of the disc b the eifective radius x for the piston rod h is as small as possible.

It is thought that the invention and its advantages will be understood from the foregoing description and it is apparent that various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the invention or sacrificing its material advantages, the form hereinbefore described and illustrated in the drawing being merely a preferred embodiment thereof.

We claim: 1

1. Loading device for a safety valve such as an explosion door for the gas chamber of a blast furnace gas collector comprising a casing having a valve seat, a lever pivotally mounted on said casing, a locking cap mounted on said lever adapted to be seated on said seat, a pivotally mounted cylinder spaced from said casing, a piston in said cylinder, a piston rod connected to said piston and to said lever, means for supplying compressed air to said cylinder so that said air may be compressed at an abnormal increase of pressure within said gas chamber by said locking cap and thereby act as an elastic pillow for said cap.

2. A loading device as set forth in claim 1 wherein a bracket is mounted upon said casing and said lever and said cylinder are pivotally mounted upon said bracket.

3. Loading device for a safety valve such as an explosion door for the gas chamber of a blast furnace gas collector comprising a locking cap, a casing having a seat for said cap, a cylinder spaced from said casing, a piston in said cylinder, a piston rod connected to said piston and to said cap, means for supplying compressed air to said cylinder so that said air may be compressed at an References Cited in the file of this patent UNITED STATES PATENTS 1,173,966 Hinkson Feb. 29, 1916 1,457,505 Curran June 5, 1923 1,889,256 Lipscomb Nov. 29, 1932 2,019,502 Osgood Nov. 5, 1935 2,250,021 Hofer July 22, 1941 2,506,162 Metzgar May 2, 1950 2,704,086 Casali Mar. 15, 1955 2,751,183 Crookston June 19, 1956 2,809,011 Davis Oct. 8, 1957 Lamb Nov. 10, 1959 

